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/// <summary><br /> /// Create a TextLabel for each bar in the GraphPane.<br /> /// Call this method only after calling AxisChange()<br /> /// </summary><br /> /// <remarks><br /> /// This method will go through the bars, create a label that corresponds to the bar value, and place it on the graph depending on user preferences. This works for horizontal or vertical bars in clusters or stacks.<br /> /// </remarks><br /> /// <param name="pane">The GraphPane in which to place the text labels.</param><br /> /// <param name="isBarCenter">true to center the labels inside the bars, false to place the labels just above the top of the bar.</param><br /> /// <param name="valueFormat">The double.ToString string format to use for creating the labels</param><br /> private void CreateBarLabels(GraphPane pane, bool isBarCenter, string valueFormat)<br /> {<br /> bool isVertical = pane.BarSettings.Base == BarBase.X;</p> <p> // Make the gap between the bars and the labels = 3% of the axis range<br /> float labelOffset;<br /> if (isVertical)<br /> labelOffset = (float)(pane.YAxis.Scale.Max - pane.YAxis.Scale.Min) * 0.03f;<br /> else<br /> labelOffset = (float)(pane.XAxis.Scale.Max - pane.XAxis.Scale.Min) * 0.03f;</p> <p> // keep a count of the number of BarItems<br /> int curveIndex = 0;</p> <p> // Get a valuehandler to do some calculations for us<br /> ValueHandler valueHandler = new ValueHandler(pane, true);</p> <p> // Loop through each curve in the list<br /> foreach (CurveItem curve in pane.CurveList)<br /> {<br /> // work with BarItems only<br /> BarItem bar = curve as BarItem;<br /> if (bar != null)<br /> {<br /> IPointList points = curve.Points;</p> <p> // Loop through each point in the BarItem<br /> for (int i = 0; i < points.Count; i++)<br /> {<br /> // Get the high, low and base values for the current bar<br /> // note that this method will automatically calculate the "effective" values if the bar is stacked<br /> double baseVal, lowVal, hiVal;<br /> valueHandler.GetValues(curve, i, out baseVal, out lowVal, out hiVal);</p> <p> // Get the value that corresponds to the center of the bar base<br /> // This method figures out how the bars are positioned within a cluster<br /> float centerVal = (float)valueHandler.BarCenterValue(bar,<br /> bar.GetBarWidth(pane), i, baseVal, curveIndex);</p> <p> // Create a text label -- note that we have to go back to the original point<br /> // data for this, since hiVal and lowVal could be "effective" values from a bar stack<br /> string barLabelText = (isVertical ? points[i].Y : points[i].X).ToString(valueFormat);</p> <p> // Calculate the position of the label -- this is either the X or the Y coordinate depending on whether they are horizontal or vertical bars, respectively<br /> float position;<br /> if (isBarCenter)<br /> position = (float)(hiVal + lowVal) / 2.0f;<br /> else<br /> position = (float)hiVal + labelOffset;</p> <p> // Create the new TextObj<br /> TextObj label;<br /> if (isVertical)<br /> label = new TextObj(barLabelText, centerVal, position);<br /> else<br /> label = new TextObj(barLabelText, position, centerVal);</p> <p> // Configure the TextObj<br /> //label.Location.CoordinateFrame = CoordType.AxisXYScale;<br /> label.FontSpec.Size = 12;<br /> label.FontSpec.FontColor = Color.RosyBrown;<br /> //label.FontSpec.Angle = 0;<br /> label.Location.AlignH = AlignH.Center;<br /> //label.Location.AlignV = AlignV.Center;<br /> label.FontSpec.Border.IsVisible = false;<br /> label.FontSpec.Fill.IsVisible = false;</p> <p> // Add the TextObj to the GraphPane<br /> pane.GraphObjList.Add(label);<br /> }<br /> }<br /> curveIndex++;<br /> }<br /> }

代码出处：http://zedgraph.org/wiki/index.php?title=Horizontal_Bar_With_Labels_Demo_v4